Consolidated Statements of Cash Flows - USD ($)	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating activities:
Net Income	$ 112,201,000	$ 98,459,000
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for probable loan losses	9,096,000	14,884,000
Specific reserve, other real estate owned	330,000	2,116,000
Depreciation of bank premises and equipment	18,936,000	18,563,000
Gain on sale of bank premises and equipment	(30,000)	(226,000)
(Gain) loss on sale of other real estate owned	(267,000)	42,000
Accretion of investment securities discounts	(307,000)	(406,000)
Amortization of investment securities premiums	18,068,000	19,142,000
Investment securities transactions, net	1,612,000	1,705,000
Impairment charges on available for sale securities		281,000
Amortization of identified intangible assets	25,000	96,000
Stock based compensation expense	699,000	822,000
Earnings from affiliates and other investments	(9,538,000)	(9,134,000)
Deferred tax (benefit) expense	(26,000)	6,752,000
(Increase) decrease in accrued interest receivable	(106,000)	2,616,000
Decrease in other assets	6,516,000	2,023,000
Net increase (decrease) in other liabilities	17,314,000	(1,028,000)
Net cash provided by operating activities	174,523,000	156,707,000
Investing activities:
Proceeds from sales and calls of available for sale securities	279,419,000	326,037,000
Purchases of available for sale securities	(944,241,000)	(1,190,066,000)
Principal collected on mortgage-backed securities	573,713,000	661,261,000
Net (increase) decrease in loans	(245,019,000)	43,857,000
Purchases of other investments	(10,282,000)	(45,622,000)
Distributions from other investments	349,000	18,368,000
Purchases of bank premises and equipment	(10,303,000)	(12,580,000)
Proceeds from sales of bank premises and equipment	11,139,000	7,956,000
Proceeds from sales of other real estate owned	2,194,000	310,000
Net cash used in by investing activities	(343,031,000)	(190,479,000)
Financing activities:
Net increase in non-interest bearing demand deposits	86,778,000	59,525,000
Net increase in savings and interest bearing demand deposits	49,654,000	62,415,000
Net decrease in time deposits	(132,980,000)	(111,878,000)
Net decrease in securities sold under repurchase agreements	(126,952,000)	(94,873,000)
Net increase in other borrowed funds	334,125,000	121,250,000
Purchase of treasury stock	(132,000)	(7,959,000)
Proceeds from stock transactions	1,185,000	259,000
Payments of cash dividends - common	(21,793,000)	(19,123,000)
Net cash provided by financing activities	189,885,000	9,616,000
Increase (decrease) in cash and cash equivalents	21,377,000	(24,156,000)
Cash and cash equivalents at beginning of period	269,198,000	273,053,000
Cash and cash equivalents at end of period	290,575,000	248,897,000
Supplemental cash flow information:
Interest paid	9,735,000	33,345,000
Income taxes paid	54,442,000	41,489,000
Non-cash investing and financing activities:
Net transfer from loans to other real estate owned	1,538,000	1,983,000
Dividends declared, not yet paid on common stock	$ 21,801,000	$ 20,446,000